Open Source Perst Embedded Database Receives Major Upgrade
Jun 3rd, 16:04 UTC
McObject has released Perst 3.0, a major upgrade to its open source, object-oriented embedded database system.
Developers working with the new Perst version 3.0 all-Java embedded database will benefit from improvements including built in full-text search, and powerful compression in embedded Java. The release also offers enhanced documentation via a new 38-page Introduction and Tutorial that leads users through Perst's features and design principles step-by-step, with ample code illustrations.
Perst's built-in full-text search improves on the database's earlier integration with the open source Apache Lucene information retrieval library. By making full-text search a native Perst feature, the embedded database gains greater efficiency compared to the earlier approach, and a smaller footprint (the Lucene .jar file is several hundred kilobytes in size, while including search capability in Perst adds just a few kilobytes).
Perst's new full-text search feature uses a standard b-tree to store an inverse index of keywords, with parsing and stemming of indexed text performed either by user-defined code or by Perst's default simple parser and stemmer. Logical operators are supported. For documents matching a query, Perst calculates the relevance of the document to the query.
Memory and storage footprint are major concerns for developers in Java ME, the Java variant for mobile and embedded devices. Perst Lite, for Java ME, adds powerful on-the-fly compression in version 3.0 that reduces stored data's size by three to five times, on average. Coupled with the database system's already-small footprint, this compression adds another compelling reason for developers to choose Perst Lite for data management on smartphones, PDAs and other small-profile devices.
Perst 3.0 marks improvements in the embedded database's documentation. McObject has added a concise new 38-page Tutorial and Introduction that guides users through Perst's features and design principles, using both explanation and code examples. Sections range from the basics - such as creating, opening and storing objects in a database - to advanced topics including schema evolution and database replication.
Perst and Perst Lite 3.0, with full source code, are available for free download from McObject's Perst download page.
(Submitted by Theodore Kenney of McObject)
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